The influence of a back-mounted hydration system (BMHS) on fluid balance during downhill skiing was investigated. Intermediate to expert skiers (N = 14), divided into two groups, alternated skiing one day with the BMHS and the other without. Fluid ingestion was on demand.

Skiers consumed more fluid per day when wearing the BMHS. During the no-fluid day, skiers drank significantly more at lunch than the during BMHS day.

The BMHS trial allowed skiers to maintain better hydration levels than in the no-fluid trial. On a no-fluid day, skiers were unable to completely rehydrate over the lunch break despite having unrestricted access to fluids. Skiers felt significantly better during skiing with the BMHS than during the no-fluid trial.